1. Field of the Invention
The present invention relates to an image forming apparatus.
2. Description of the Related Art
Conventionally, there is known an image forming apparatus, such as a copier, including a paper feeding tray unit, which is referred to as PFU (paper Feeder Unit), having a plurality of paper feeding trays, so that a large number of sheets of paper are able to be fed thereinto. There is also known an image forming apparatus having a mechanism to perform printing processing on both sides of paper (double-sided printing) in addition to printing processing on one side of paper (single-sided printing).
If a paper jam occurs in these image forming apparatuses, the image forming apparatuses immediately stop carrying sheets of paper. In order to restart the image forming apparatuses, it is necessary to remove the jammed sheet jammed therein.
However, for example, in a case where a large number of sheets of paper are carried in an image forming apparatus during processing, such as a case where an image forming apparatus having a PFU performs double-sided printing, it is necessary to remove not only a jammed sheet but also sheets being carried (remaining sheets) in the image forming apparatus when a jam occurs. Accordingly, there is a plurality of locations from which the sheets need to be removed, so that it takes time and trouble to recover the image forming apparatus.
Then, for example, Japanese Patent Application Laid-Open Publication No. 2002-268299 proposes a technology to, when a jam occurs, carry remaining sheets to a reverse paper path which reverses sheets of paper, the remaining sheets being in locations which seem no problem for the remaining sheets therein to continue to be carried, and to remove the remaining sheets from the reverse paper path in a lump.
However, because the technology proposed by the Japanese Patent Application Laid-Open Publication No. 2002-268299 is a technology to accumulate remaining sheets on a reverse paper path, it is difficult to remove the accumulated remaining sheets.
In addition, the technology proposed by the Japanese Patent Application Laid-Open Publication No. 2002-268299 does not take the sizes of the remaining sheets into account, and hence, regardless of the sizes of the remaining sheets, the accumulation is performed in the same manner. Consequently, there is a possibility that a secondary jam is caused by the accumulation, or the apparatus is damaged thereby and the like.